STRATA EXPOSED IN CONSTRUCTING FILTON-AVONMOUTH RAILWAY. 7 
The White Lias is represented by a single bed with sun bed 
characters ; further West it becomes thicker. The Pleuromya and 
Ostrea series follow — Pleuj'omya crowcombeia is abundant in the lower 
portion, becoming rare about two feet above the White Lias where 
Ostrea liassica is the commonest fossil. 
The most notable circumstance of the Filton cutting is the apparent 
absence of the Ammonite, Psilonotoceras planorhis^ which in this 
district is usually in evidence just above the Ostrea beds. The only 
Ammonite found at Filton belongs to the Am. torus group, viz., 
Caloceras Johnstoni. This species enters abruptly and is abundant ; it 
indicates a later date than Am. planorbis. 
The clays in the upper part of the section have yielded no fossils 
that would identify them. It may be remarked, however, that in 
most of the local sections, the angulatus zone is ushered in by similar 
thick clays or shales. 
The upper portion of the vertical section (down to the White Lias) 
was constructed from data supplied by the Filton cutting. 
Lower 
Lias I 
Upper 
Rh^tic ' 
Lower ' 
Rh^etic 
Keuper < 
V 
Torus beds 
Ostrea and j 
Pleuromya beds | 
White Lias ( 
Gotham marble 
Estheria beds 
Upper Pecten bed 
Lower Pecten bed 
Bone bed 
Nodular band of \ 
brecciated limestone/ 
Tea- green marl 
Red marl 
Reptiles 
Am. (Caloceras) Johnstoni 
Ostrea liassica 
Pleuromya crowcombeia 
Modiola 
Darivinula 
Estheria and Naiadita 
Pecten valoniensis 
§. Pleurophorus elongatus 
s Avicida contorta 
§ Schizodus Eivaldi 
^ Vertebrates 
a 
Vertical section of the strata exposed in the Filton and Charlton 
Railway Cuttings. 
